In the Wideband Code Division Multiple Access (W-CDMA) being one of the radio access systems, a communication between a mobile station (UE: User Equipment) and a radio access network (UTRAN: Universal Terrestrial Radio Access Network) is performed according to the Radio Link Control (RLC) protocol.
Further, in some cases, a re-establishment of data is made in the RLC layer following the RLC protocol (for example, refer to the Non-patent Document 1).
[Non-patent Document 1] 3GPP TSG-RAN, “TS25.322 V6.1.0 Radio Link Control (RLC) protocol specification”, September, 2004.
However, when data has been re-established, in some cases, a reception device sometimes discards data before completely receiving the whole data, or, a transmission device sometimes discards data before receiving an acknowledgement of receipt of the whole data. In this way, there has been a problem that a data loss occurs.